Ti22Al25Nb Powder

Overview of Ti22Al25Nb Powder

Ti22Al25Nb belongs to the class of titanium aluminide alloys that possess attractive properties like high specific strength, good creep resistance, oxidation resistance, and ability to withstand extreme temperatures. The near-equiatomic ratio of titanium and aluminum provides a balanced combination of light weight, strength and environmental resistance at elevated temperatures.

Key characteristics of Ti22Al25Nb powder include:

• Very high specific strength (strength-to-weight ratio)
• Excellent high temperature mechanical properties
• Good creep and fatigue strength
• Low density compared to nickel and iron-based superalloys
• Outstanding corrosion resistance

Ti22Al25Nb powder has emerged as an excellent choice for reducing weight and improving efficiency in aerospace, automotive, and other high-performance applications at elevated temperatures.

Composition of Ti22Al25Nb Powder

Ti22Al25Nb powder has the following nominal composition:

Element	Weight %
Titanium (Ti)	22%
Aluminum (Al)	25%
Niobium (Nb)	5-10%
Vanadium (V)	0-5%
Chromium (Cr)	0-2%
Carbon (C)	0-0.2%
Oxygen (O)	0-0.2%

The amounts of strengthening elements like niobium and vanadium can be varied to optimize the mechanical properties. Impurity levels of carbon and oxygen are minimized.

Properties of Ti22Al25Nb Powder

Key properties of Ti22Al25Nb powder include:

Property	Value
Density	3.7-3.9 g/cm3
Melting Point	1350-1450¡«C
Thermal Conductivity	16-22 W/mK
Electrical Resistivity	1.7 Ã×´Î.cm
Young’s Modulus	160-180 GPa
Poisson’s Ratio	0.32-0.34
Tensile Strength	500-900 MPa
Yield Strength	400-600 MPa
Elongation	1-4%
Creep Strength	150-300 MPa
Oxidation Resistance	Excellent up to 800¡«C

 

The properties like high strength, low density, and temperature capability make it well suited for critical aerospace components needing weight savings.

Production Method for Ti22Al25Nb Powder

Ti22Al25Nb powder can be produced via methods like:

• Gas Atomization?- High pressure inert gas jet used to atomize molten alloy resulting in fine spherical powder ideal for AM.
• Plasma Rotating Electrode Process (PREP)?- Centrifugal disintegration of rapidly rotating molten metal into fine droplets yields spherical powder.
• Mechanical Alloying?- High energy ball milling of elemental/pre-alloyed powders followed by annealing and secondary atomization.

Gas atomization and PREP allow excellent control over powder characteristics like particle size distribution, morphology, and microcleanliness.

Applications of Ti22Al25Nb Powder

Ti22Al25Nb powder is used in:

• Additive Manufacturing?- Selective laser melting to produce complex lightweight components like brackets, airfoils, impellers for aerospace and automotive.
• Thermal Spray Coatings?- Applied via plasma or HVOF spraying to provide wear/corrosion resistance for turbocharger blades and aerospace components at high temperatures.
• Metal Injection Molding?- To manufacture small, complex net-shape parts needing high specific strength up to 800¡«C like turbine blades.
• Powder Metallurgy?- Pressing and sintering to create low-density, high-strength parts like connecting rods.

Specifications of Ti22Al25Nb Powder

Ti22Al25Nb powder is available under various size ranges, shapes and purity levels:

• Particle Size:?From 15-45 Ã×m for AM methods, up to 100 Ã×m for thermal spray processes.
• Morphology:?Near-spherical powder morphology provides optimal flow and packing density.
• Purity:?From commercial to high purity levels based on impurity limits and process requirements.
• Oxygen Content:?Levels maintained below 2000 ppm for most applications.
• Flowability:?Powder customized for excellent flow rates above 25 s/50 g.

Global Suppliers of Ti22Al25Nb Powder

Some of the major global suppliers of Ti22Al25Nb powder are:

• AP&C (Canada)
• TLS Technik (Germany)
• Sandvik Osprey (UK)
• Tekna (Canada)
• ECKA Granules (Germany)
• Titanium Powder (Russia)

These companies produce various grades of Ti22Al25Nb powder tailored for additive manufacturing, thermal spray, powder metallurgy and other applications.

Pricing of Ti22Al25Nb Powder

Ti22Al25Nb powder is priced higher than steels and nickel alloys:

• Quantity?- $100-150 per kg for bulk orders above 500 kg. Smaller quantities are priced significantly higher.
• Quality?- High purity, spherical powder manufactured under tightly controlled conditions using advanced processes demands premium pricing.
• Supplier?- Major global suppliers offer cost advantages compared to smaller manufacturers due to higher production volumes.
• Geography?- Prices vary across regions with Europe and North America being higher priced markets compared to Asia.

For critical applications, buyers should focus on quality rather than lowest cost while sourcing Ti22Al25Nb powder.

Storage and Handling of Ti22Al25Nb Powder

Ti22Al25Nb powder requires careful storage and handling:

• Should be stored in sealed containers under inert gas like argon to prevent oxidation
• Avoid accumulation of fine powder to minimize risk of dust explosions
• Use proper PPE, ventilation, grounding and safety practices during powder handling
• Prevent contact between powder and ignition sources due to flammability hazard
• Follow applicable safety guidelines from supplier SDS

Care should be taken when handling this highly reactive alloy powder.

Inspection and Testing of Ti22Al25Nb Powder

Key quality control tests performed on Ti22Al25Nb powder:

• Chemical analysis using ICP-OES or XRF to ensure composition meets specifications
• Particle size distribution using laser diffraction as per ASTM B822 standard
• Morphology analysis through SEM imaging
• Powder flow rate measurement using Hall flowmeter as per ASTM B213 standard
• Density measurement by helium pycnometry
• Impurity analysis through inert gas fusion or ICP-MS
• Microstructure characterization by X-ray diffraction

Thorough testing ensures batch consistency and powder quality for the intended application.

Comparison Between Ti22Al25Nb and Inconel 718 Powders

Ti22Al25Nb and Inconel 718 powders compared:

Parameter	Ti22Al25Nb	Inconel 718
Density	3.7-3.9 g/cm3	8.2 g/cm3
High temperature strength	Comparable	Comparable
Oxidation resistance	Better	Good
Cost	Higher	Lower
Workability	Poor	Excellent
Applications	Aerospace components	Aerospace, automotive
Availability	Moderate	Readily available

 

Ti22Al25Nb offers weight savings over Inconel 718. But workability is poor and cost is higher for titanium aluminide powder.

Ti22Al25Nb Powder FAQs

Q: How is Ti22Al25Nb powder produced?

A: Ti22Al25Nb powder is commercially produced using gas atomization, plasma rotating electrode process, and mechanical alloying followed by annealing and secondary atomization.

Q: What are the main applications of Ti22Al25Nb powder?

A: The major applications include additive manufacturing, thermal spray coatings, metal injection molding, and powder metallurgy to make lightweight structural parts needing high temperature capability.

Q: What is the typical particle size used in AM?

A: For most metal AM processes, the ideal Ti22Al25Nb powder size range is 15-45 microns with high purity, spherical morphology and good powder flow.

Q: Does Ti22Al25Nb powder require special handling precautions?

A: Yes, it is highly reactive and requires careful handling under inert atmosphere using ventilation, grounding, PPE to prevent fire or explosion hazards.

Q: Where can I buy Ti22Al25Nb powder for aerospace applications?

A: For aerospace parts needing lightweight and high strength, Ti22Al25Nb powder can be sourced from leading manufacturers including AP&C, TLS Technik, Sandvik Osprey, and Tekna.